JP4946816B2 - Parking assistance device, parking assistance method, and computer program - Google Patents

Description

  The present invention relates to a parking support device, a parking support method, and a computer program that support parking of a vehicle.

  2. Description of the Related Art Conventionally, there is a parking assistance device that displays a camera image that captures the environment behind a vehicle during parking and assists a driver's parking operation with respect to the vehicle. In such a parking assistance device, the situation of the backward direction side with respect to the vehicle is displayed as an image to assist the driver's parking operation with respect to the vehicle, or the vehicle travels based on the signal from the steering angle sensor. There is known one that supports a driver's parking operation with respect to a vehicle by calculating a prediction curve and displaying the calculated progress prediction curve superimposed on the captured camera image as described above. Furthermore, the parking assist device not only simply displays an image of the rear environment, but also calculates the travel route of the vehicle until parking is completed in the target parking space, and the vehicle follows the calculated travel route. Techniques for performing steering assistance and automatic steering so that the vehicle travels are known.

Here, since the travel route calculated by the parking assistance device is calculated based on the turning performance of the vehicle, it is often a route including a sharp turn due to the maximum steering angle of the vehicle. However, in a route including such a sharp turn, the steering amount does not reach the target value when steering assistance or automatic steering is performed, and the deviation from the target route may occur due to a possibility that the turning radius becomes large, a difference in speed, or the like. There is a high risk. Thus, for example, Japanese Patent Application Laid-Open No. 2004-352110 describes a technique for setting a new travel route by correcting the steering angle of the travel route for a travel route once calculated.
JP 2004-352110 A (pages 4 to 6, FIGS. 2 and 3)

  However, in the parking assistance device described in Patent Literature 1 described above, it has not been determined whether the corrected travel route is a travel route that allows the vehicle to enter the parking space. Here, in general, obstacles such as other parked vehicles, fences, and block fences are arranged around the parking space. Therefore, even when a route that does not contact those obstacles is set in the travel route before correction, there is a possibility that the route that comes into contact with the obstacle becomes new by correcting the travel route. .

  The present invention has been made to solve the above-described problems in the prior art, and it is possible to park the travel route even after the steering angle is reduced by relaxing the steering angle in consideration of the shape of the parking space where parking is performed. An object of the present invention is to provide a parking assistance device, a parking assistance method, and a computer program that can be used as a route through which a vehicle can enter a space, and that allows easy and safe parking when parking. .

In order to achieve the above object, a parking assist device (1) according to claim 1 of the present application is provided with a predetermined amount of parking space detecting means (3) for detecting a parking space and a parking space detected by the parking space detecting means. A first travel route calculating means (3) for calculating a first travel route for entering the vehicle at a steering angle; a parking space shape acquiring means (3) for acquiring the shape of the parking space; and the parking space shape acquiring means. Based on the acquired shape of the parking space, the second travel in which the steering angle of the first travel route calculated by the first travel route calculation means is relaxed within a range in which the vehicle can enter the parking space. a second traveling path calculating means for calculating a route (3), long judging whether the route path total length than a predetermined length of said second traveling path calculated by the second traveling path calculating means all When the determination unit (3) and the route total length determination unit determine that the total length of the second travel route is longer than the predetermined distance, the total length of the second travel route is equal to or less than the predetermined distance. Based on the second travel route correction means (3) for correcting the second travel route and the second travel route calculated by the second travel route calculation means and corrected by the second travel route correction means. Parking support means (3) for supporting the vehicle.

Moreover, the parking assistance apparatus (1) according to claim 2 is the parking assistance apparatus according to claim 1, wherein the first travel route calculation means enters the parking space without contacting the vehicle or an obstacle. Calculating the first travel route including a second half route that turns from a steered position to a parking position in the parking space with a possible radius, and a first half route that turns from the reverse start position of the vehicle to the steered position. The second travel route calculation means includes a second half route that turns from the steered position to the parking position with a maximum radius that can enter the parking space without contacting the vehicle or an obstacle, and a reverse start position of the vehicle. And calculating the second travel route including the first half route that turns from the steering position to the steered position, and the second travel route correction means determines the total length of the second travel route by the route full length determination means. If it is determined that longer than away, the path length of the second travel path by reducing the turning radius of the second half path of the second travel path to correct the second travel path to a predetermined distance or less It is characterized by that.

According to a third aspect of the present invention, there is provided a parking assist method comprising: a parking space detection step (S1) for detecting a parking space; and a first vehicle for entering the parking space detected at the parking space detection step at a predetermined steering angle. The first travel route calculation step (S11 to S15) for calculating the travel route, the parking space shape acquisition step (S21) for acquiring the shape of the parking space, and the shape of the parking space acquired in the parking space shape acquisition step Based on the second travel route, the second travel route is calculated by relaxing the steering angle of the first travel route calculated in the first travel route calculation step within a range in which the vehicle can enter the parking space. a route calculation step (S22~S27), the path the entire length of said second traveling path calculated by the second traveling path calculating step Tokoro A path total length determining step for determining whether or not the distance is longer than the distance, and a path total length of the second travel path when the path total length of the second travel path is determined to be longer than the predetermined distance by the path total length determination step. A second travel route correction step for correcting the second travel route so as to be less than or equal to the predetermined distance; and the second travel route calculated by the second travel route calculation step and corrected by the second travel route correction step. And a parking support step (S5) for supporting parking based on the above.

Furthermore, the computer program according to claim 4 causes the computer to enter the vehicle at a predetermined steering angle into the parking space detection function (S1) for detecting the parking space and the parking space detected by the parking space detection function. The first travel route calculation function (S11 to S15) for calculating the first travel route, the parking space shape acquisition function (S21) for acquiring the shape of the parking space, and the parking space acquired by the parking space shape acquisition function The second travel route is calculated by relaxing the steering angle of the first travel route calculated by the first travel route calculation function within a range in which the vehicle can enter the parking space. 2 traveling path calculation function and (S22~S27), the route total length predetermined distance of the second travel path calculated by the second travel path calculation function When the total length of the second travel route is determined to be longer than the predetermined distance by the total length determination function for determining whether or not the total length of the second travel route is longer than the predetermined distance, A second travel route correction function that corrects the second travel route so as to be equal to or less than a predetermined distance; a second travel route that is calculated by the second travel route calculation function and corrected by the second travel route correction function; And a parking support function (S5) for supporting parking based on this.

According to the parking assist device according to claim 1 having the above-described configuration, the travel route is changed to the parking space even after the steering angle is reduced by relaxing the steering angle in consideration of the shape of the parking space for parking. Therefore, there is no possibility that the vehicle contacts an obstacle around the parking space when parking. Therefore, the relaxed route can reduce the driving burden on the driver and allow easy and safe parking.
Further, as a result of relaxing the steering angle, when the total length of the second travel route becomes longer than necessary, it can be shortened to an appropriate distance. As a result, the parking operation and the parking time can be simplified, and the parking space can be appropriately parked.

According to the parking assist device of the second aspect, the second traveling route can be corrected to a route having an appropriate length by reducing the turning radius of the second half route of the second traveling route. Therefore, the relaxed route can reduce the driving burden on the driver and allow easy and safe parking.

According to the parking support method of claim 3, the vehicle is moved to the parking space even after the steering angle is reduced by relaxing the steering angle in consideration of the shape of the parking space where parking is performed. It is possible to make a route where the vehicle can enter, and there is no possibility that the vehicle will come into contact with obstacles around the parking space when parking. Therefore, the relaxed route can reduce the driving burden on the driver and allow easy and safe parking.
Further, as a result of relaxing the steering angle, when the total length of the second travel route becomes longer than necessary, it can be shortened to an appropriate distance. As a result, the parking operation and the parking time can be simplified, and the parking space can be appropriately parked.

Further, according to the computer program of the fourth aspect, the vehicle is moved to the parking space even after the steering angle is relaxed by relaxing the steering angle in consideration of the shape of the parking space where parking is performed. The route can be entered, and there is no possibility that the vehicle contacts an obstacle around the parking space when parking. Therefore, the relaxed route can reduce the driving burden on the driver and allow easy and safe parking.
Further, as a result of relaxing the steering angle, when the total length of the second travel route becomes longer than necessary, it can be shortened to an appropriate distance. As a result, the parking operation and the parking time can be simplified, and the parking space can be appropriately parked.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a parking assistance device according to the present invention will be described in detail with reference to the drawings based on an embodiment that is embodied. First, a schematic configuration of the parking assistance device 1 according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic configuration diagram of a parking support apparatus 1 according to the present embodiment, and FIG. 2 is a block diagram schematically showing a control system of the parking support apparatus 1 according to the present embodiment.

  As shown in FIGS. 1 and 2, the parking assistance apparatus 1 according to the present embodiment includes a parking assistance ECU (parking space detection means, first travel route calculation means, parking space shape acquisition means) installed on the vehicle 2. , Second travel route calculation means, parking support means, route length determination means, second travel route correction means) 3, rear camera 4, obstacle sensors 5A and 5B, liquid crystal display 6, speaker 7, and vehicle It is comprised by various sensors, such as DB8, vehicle ECU9, and the vehicle speed sensor 11, the steering sensor 12, the gyro sensor 13, and the shift lever sensor 14 which were connected to parking assistance ECU3.

  The parking assist ECU (Electronic Control Unit) 3 calculates a travel route when the vehicle is parked in the detected parking space, and also assists parking of the vehicle 2 based on the calculated travel route (see FIG. 3 to FIG. 5). The parking assist ECU 3 may also be used as an ECU used for controlling the navigation device. The detailed configuration of the parking assist ECU 3 will be described later.

  The rear camera 4 uses a solid-state image sensor such as a CCD, for example, and is installed near the upper center of the license plate mounted on the rear side of the vehicle 2 and installed with the line of sight 45 degrees below the horizontal. The Then, the rear side of the vehicle that is the traveling direction of the vehicle 2 is imaged when the vehicle is moving backward, and the captured image is displayed on the liquid crystal display 6.

  The obstacle sensors 5A and 5B are installed in a pair of left and right in front of the vehicle 2, and basically include a sound wave transmitting unit and a sound wave receiving unit. Then, an ultrasonic wave is emitted from the sound wave transmission unit in the left-right direction of the vehicle 2 and a reflected wave reflected by an obstacle (specifically, a parked vehicle, a block fence or the like) is received by the sound wave reception unit. As a result, the parking assist ECU 3 can detect the distance to the obstacle located around the vehicle 2 based on the time from the reception of the ultrasonic wave to the reception of the reflected wave. And in this embodiment, parking assistance ECU3 specifies the shape of the detected parking space, and the detection of the parking space located around a vehicle further based on the detection result of obstacle sensor 5A, 5B.

  The liquid crystal display 6 is provided on the center console or panel surface in the room of the vehicle 2 and parking assistance processing described later with respect to the vehicle rear image captured by the rear camera 4 when parking (see FIGS. 3 to 5). The travel route calculated by is superimposed and displayed. The liquid crystal display 6 may also be used as a navigation device.

  The speaker 7 is provided on the center console or the panel surface in the room of the vehicle 2 and outputs a guidance voice, a warning sound, etc. regarding driving support. In particular, the parking assistance device 1 according to the present embodiment outputs guidance sound for turning timing and turning angle of the steering when the vehicle is parked.

The vehicle DB 8 is a storage unit that stores various parameter information related to the vehicle such as the shape design value of the vehicle 2 and the camera design value. For example, the vehicle DB 8 stores the wheel radius, vehicle length, vehicle width, vehicle height, wheel base, minimum turning radius, the optical axis direction of the rear camera 4, the installation position of the rear camera 4 with respect to the vehicle 2, and the like. Yes.
And parking assistance ECU3 calculates the driving | running route to a parking space by the parking assistance process (refer FIGS. 3-5) mentioned later by using the various parameter information memorize | stored in vehicle DB8 so that it may mention later. Similarly, by using various parameter information stored in the vehicle DB 8, parking assistance (guidance and automatic steering) of the vehicle 2 based on the calculated travel route is performed.

  The vehicle ECU 9 is an electronic control unit of the vehicle 2 that controls the operation of the engine, transmission, accelerator, brake, and the like, and is connected to a steering, a brake actuator, an accelerator actuator, an AT (Automatic Transmission), and the like. Then, the vehicle ECU 9 changes the steering angle, the brake pressure, the amount of air sucked into the engine, the gear ratio, and the like based on an instruction from the parking assistance ECU 3 during parking, and a parking assistance process described later (see FIGS. 3 to 5). It is possible to perform automatic steering along the travel route calculated in (1).

  The vehicle speed sensor 11 is a sensor for detecting a moving distance and a vehicle speed of the vehicle, generates a pulse according to the rotation of the wheel of the vehicle 2, and outputs a pulse signal to the parking assist ECU 3. And parking assistance ECU3 calculates the rotational speed and moving distance of a wheel by counting the generated pulse.

The steering sensor 12 is a sensor that is attached to the inside of the steering device and that can detect the turning angle of the steering.
The gyro sensor 13 is a sensor that can detect the turning angle of the vehicle 2. Further, by integrating the turning angle detected by the gyro sensor 13, the vehicle direction can be detected.
The shift lever sensor 14 is built in a shift lever (not shown), and the shift position is “P (parking)”, “N (neutral)”, “R (reverse)”, “D (drive)”, “2”. It is possible to detect which position is (second) or “L (low)”.

  Next, the details of the parking assistance ECU 3 will be described with reference to FIG. 2. The parking assistance ECU 3 is configured with the CPU 21 as a core, and a ROM 22 and a RAM 23 which are storage means are connected to the CPU 21. The ROM 22 stores a parking assistance processing program (see FIGS. 3 to 5), which will be described later, and various other programs necessary for controlling the rear camera 4 and the obstacle sensors 5A and 5B. The RAM 23 is a memory for temporarily storing various data calculated by the CPU 21.

  Then, the parking assistance processing program which parking assistance ECU3 of the parking assistance apparatus 1 which concerns on this embodiment which has the said structure performs is demonstrated based on FIG. FIG. 3 is a flowchart of a parking assistance processing program in the parking assistance apparatus 1 according to the present embodiment. Here, the parking assistance processing program is repeatedly executed at predetermined intervals (for example, every 200 ms) after the ignition is turned on, and performs a process of calculating a travel route for allowing the vehicle to enter the parking space detected at the time of parking. It is a program. The programs shown in the flowcharts of FIGS. 3 to 5 below are stored in the ROM 22 and the RAM 23 provided in the parking assist ECU 3 and are executed by the CPU 21. In the embodiment described below, parking assistance in the case of performing parallel parking will be described.

First, in step (hereinafter abbreviated as S) 1 in the parking assistance processing program, the CPU 21 detects a parking space around the own vehicle based on the detection results of the obstacle sensors 5A and 5B. Moreover, it identifies from the detection result about the shape of the detected parking space.
Specifically, as the vehicle moves, the obstacle sensors 5A and 5B detect the width of the empty space in the parking lot or on the side of the road. Further, the vertical width of the empty space is detected based on the detection result of the horizontal width after passing through the empty space. And based on the shape of the own vehicle memorize | stored in vehicle DB8, it determines with it being an empty space of the width which can park the own vehicle (For example, vehicle width + width of 30 cm or more and vehicle length + vertical width of 1 m or more) In such a case, the empty space is detected as a parking space. Further, the shape of the parking space is specified based on the detected horizontal width and vertical width.
In addition, it is good also as performing detection of a parking space and acquisition of the shape of a parking space by imaging the surrounding environment of the own vehicle with a camera, and performing an image recognition process to a captured image. Moreover, you may make it acquire a parking space shape from DB or a center. In addition, said S1 is corresponded to the process of a parking space detection means.

  Next, in S2, CPU21 determines whether the parking assistance starting trigger was set to ON. In the present embodiment, the parking assistance activation trigger is turned on when an available space that can be parked is detected or when a predetermined operation is performed by the user using an operation button (not shown).

  And when it determines with the parking assistance starting trigger having been set to ON (S2: YES), it transfers to S3. On the other hand, when it is determined that the parking support activation trigger is OFF (S2: NO), the parking support processing program is terminated without performing parking support.

  In S <b> 3, the CPU 21 performs a first travel route calculation process (FIG. 4) based on a fixed steering angle turning described later. In the first travel route calculation process, the first reverse start position and the parking target position are set based on the current position of the host vehicle and the shape of the parking space detected in S1, and the parking route by the fixed steering angle turning is set to the first. Calculate as one travel route.

  Subsequently, in S4, the CPU 21 performs a second travel route calculation process (FIG. 5) based on the relaxation of the steering angle described later. In the second travel route calculation process, the second travel route is calculated by relaxing the steering angle of the first travel route calculated in S3, and the calculated second travel route is corrected as necessary. .

Thereafter, in S5, the CPU 21 performs a parking support process for supporting parking of the host vehicle based on the second travel route calculated in S4. Specifically, steering assistance or automatic steering is performed so that the host vehicle follows the calculated second travel route.
Here, as the steering assistance, for example, the calculated travel route is superimposed and displayed on the vehicle rear image. Further, a guidance sound for turning timing and turning angle of the steering is output from the speaker 7.
On the other hand, as the automatic steering, for example, an instruction signal is transmitted to the vehicle ECU 9 to change the steering angle, the brake pressure, the amount of air sucked into the engine, the gear ratio, etc., and the vehicle automatically follows the travel route. Control to run. In addition, said S5 is corresponded to the process of a parking assistance means.

  Next, a sub-process of the first travel route calculation process executed by the parking assist ECU 3 in S3 will be described with reference to FIG. FIG. 4 is a flowchart of a sub-processing program of the first travel route calculation process according to the present embodiment.

  In the first travel route calculation process, first, in S11, the CPU 21 sets a target position for parking the own vehicle in the parking space detected in S1 (that is, the position of the own vehicle when the parking is completed). Further, in S12, the CPU 21 determines the first reverse start position when the host vehicle is parked in the parking space detected in S1 according to the first travel route (that is, the position of the host vehicle starting to reverse for parking). Set. The target position is set based on the detected shape of the parking space and a predetermined fixed value (A and B in FIG. 6). Further, the first reverse start position is set based on the current host vehicle position and a predetermined fixed value (C in FIG. 6).

Hereinafter, an example of the target position and first reverse start position setting process executed in S11 and S12 will be described with reference to FIG. In FIG. 6, the target position 32 and the first reverse start position 33 set when the vehicle 2 detects the parking space 31 will be described.
As shown in FIG. 6, the target position 32 is set to a position separated from the left edge of the parking space 31 by A and separated from the rear edge by B. A and B are predetermined fixed values (for example, A = 30 cm, B = 30 cm).
On the other hand, as shown in FIG. 6, the first reverse start position 33 is set to a position ahead of the current position of the host vehicle in the traveling direction and forward by C from the front edge of the parking space 31. C is a predetermined fixed value (for example, C = 2 m).

  Subsequently, in S <b> 13, the CPU 21 sets a second turning radius that is a turning radius in the second half route from the steered position where the driver steers in the first travel route to the target position. In the present embodiment, the second turning radius of the first travel route is an arbitrary radius that satisfies a condition that allows the vehicle to enter the parking space without contacting an obstacle.

  Furthermore, in S14, the CPU 21 sets a first turning radius that is a turning radius in the first half path from the first reverse start position to the steered position. In the present embodiment, the first turning radius is the radius of a circle that passes through the first retreat start position and is in contact with the second half path that turns with the second turning radius. Further, the point where the first half path and the second half path are in contact with each other is the steered position of the first travel path.

Hereinafter, an example of setting processing of the first turning radius and the second turning radius executed in S13 and S14 will be described with reference to FIG. In FIG. 7, the first turning radius and the second turning radius that are set when the vehicle 2 detects the parking space 31 will be described.
As shown in FIG. 7, the second turning radius R2 is set to the minimum turning radius. Thereby, the circle 35 including the latter half route that is the parking route from the steered position P to the target position 32 is specified.
On the other hand, as shown in FIG. 7, the first turning radius R1 is set to the radius of a circle 36 that passes through the first retreat start position 33 and contacts the circle 35 that turns with the second turning radius R2. Thereby, the circle 36 including the first half path that is the parking path from the first reverse start position 33 to the steered position P is specified. Further, the point where the circle 35 and the circle 36 are in contact becomes the steered position P of the first travel route.

  Next, in S15, the CPU 21 calculates the first travel route according to the parameters set in S11 to S14. Specifically, (a) a preparation path that advances from the current vehicle position to the first reverse start position, and (b) a first half path that turns from the first reverse start position to the steered position by the first turning radius, (C) The first traveling route is a combination of the second half route of turning from the steered position to the target position with the second turning radius.

Hereinafter, an example of the first travel route calculation process executed in S15 will be described with reference to FIG. In FIG. 8, the first travel route 37 calculated when the first reverse start position 33, the target position 32, the first turning radius R1, and the second turning radius R2 shown in FIG. 7 are set will be described.
As shown in FIG. 8, the first travel path 37 includes a preparation path 38 that moves forward from the current host vehicle position to the first reverse start position 33, and a steered position P by the first turning radius R <b> 1 from the first reverse start position 33. And a first half path 39 that turns to the target position 32 by the second turning radius R2 from the steered position P. The vehicle 2 travels along the first travel route 37, thereby allowing the vehicle 2 to enter the target position 32 in the parking space 31.
In addition, said S11-S15 is corresponded to the process of a 1st driving | running route calculation means. Further, in the present embodiment, a case where the vehicle performs parking in parallel will be described. However, when parking other than parallel parking, there is no steered position and the same from the set first reverse start position to the target position. The first travel route is constituted by a turning route that turns with a turning radius of.

  Next, a sub-process of the second travel route calculation process executed by the parking assistance ECU 3 in S4 will be described with reference to FIG. FIG. 5 is a flowchart of a sub-processing program of the second travel route calculation process according to the present embodiment.

  First, in S21, the CPU 21 acquires the shape of the parking space 31 specified in S1. In addition, said S21 corresponds to the process of a parking space acquisition means.

  Next, in S22, the CPU 21 first calculates the second turning radius of the second travel route in order to calculate the second travel route in which the steering angle of the first travel route calculated in S15 is relaxed. The second turning radius is the turning radius in the second half path from the turning position where the driver steers as described above to the target position. In particular, in the present embodiment, the second turning radius of the second traveling path is: The maximum radius that allows the vehicle to enter the parking space without touching obstacles.

  Hereinafter, the calculation process of the second turning radius of the second travel route executed in S22 will be described in more detail with reference to FIGS. 9 and 10. Here, as a calculation method of the second turning radius of the second travel route, there are (a) a calculation method using a three-square theorem and (b) a calculation method using a table.

First, an example of a calculation method using the three square theorem will be described with reference to FIG.
As shown in FIG. 9, an arc 41 having a center I on the extension line of the rear axle and passing through the left front corner J of the vehicle and the end point K of the parking space 31 is drawn, and the radius R3 is calculated.
Thereafter, using the calculated radius R3, the distance L from the left front angle J of the vehicle acquired from the vehicle DB 8 to the rear wheel axle, and the vehicle width W, the CPU 21 uses the following formula (1) using the three square theorem. A second turning radius R4 is calculated.
R4 = (R3 ² −L ² ) ^1/2 −W / 2 (1)

Next, an example of a calculation method using a table will be described based on FIG.
As shown in FIG. 10, a table in which the space length (vertical width) of the parking space 31 and the second turning radius R4 are associated with each other is stored in advance in a DB or the like. And the 2nd turning radius R4 is specified from the space length of a parking space especially among the shapes of the parking space acquired by said S31. In addition, it is desirable to provide an upper limit (for example, 10 m) for the value of the second turning radius R4 in the table. By providing this upper limit, it is possible to prevent the entire length of the second travel route 42 from becoming too long.

Next, in S23, the CPU 21 determines whether or not the total length of the second travel route using the second turning radius R4 calculated in S22 is longer than a predetermined distance. Here, as shown in FIG. 11, the second travel route is a route having a second half route that turns with the second turning radius R4, and the steering angle is relaxed compared to the first travel route 37, and the parking operation is easy. Become. However, if the total path length D of the second travel path 42 becomes too long by relaxing the steering angle, it is difficult to park along such a long path. Therefore, after the following S23, the second travel route 42 is corrected when the overall length D of the second travel route 42 becomes too long.
Since the total length D of the second travel route 42 becomes longer as the second turning radius R4 becomes larger, the route of the second traveling route 42 is determined when the second turning radius R4 is larger than a predetermined value in S23. It is determined that the total length D is longer than the predetermined distance. The predetermined value used for the determination is, for example, the reverse start position when the first turning radius is set to the same value as the second turning radius, which is several times the minimum turning radius (for example, 3 to 5 times). There is a radius or the like that is a predetermined distance or more away from the parking space 31 (for example, 10 m). Further, the above S23 corresponds to the processing of the route total length determining means.

  Note that the process of S23 is performed only when the third square theorem is used when calculating the second turning radius in S22, and is not performed when a table is used.

  If it is determined in S23 that the total length D of the second travel route 42 is longer than the predetermined distance, that is, the second turning radius R4 of the second travel route is larger than the predetermined value, the process proceeds to S24. Transition.

  In S24, the CPU 21 corrects the second travel route 42 to be within a predetermined distance by correcting the second turning radius R4 calculated in S22 to a predetermined value or less. The predetermined value is the same value as the value used for the determination in S23. Further, S24 corresponds to the processing of the second travel route correcting means.

  On the other hand, if it is determined in S23 that the total length D of the second travel route 42 is equal to or smaller than the predetermined distance, that is, the second turning radius R4 of the second travel route is equal to or smaller than the predetermined value, the second travel route 42 The process proceeds to S25 without correcting the route.

  In S25, the CPU 21 calculates, as the first turning radius, the same radius as the second turning radius calculated in S22 (or the corrected second turning radius when correction is performed in S24). The first turning radius is the turning radius in the first half path from the reverse start position where the driver steers as described above to the steered position.

  Subsequently, in S26, the CPU 21 starts the second reverse start position when parking the own vehicle in the parking space detected in S1 according to the second travel route with a relaxed steering angle (that is, starts reverse for parking). Set the position of your vehicle.

An example of the first turning radius calculation process executed in S25 and the second reverse start position setting process executed in S26 will be described below with reference to FIG. In FIG. 12, the first turning radius and the second reverse start position calculated when the vehicle 2 detects the parking space 31 will be described.
As described above, the second turning radius R4 is set to the maximum radius at which the left front corner J of the vehicle when turning with the second turning radius R4 does not come into contact with an obstacle. Thereby, the circle 43 including the second half route that is the parking route from the steered position to the target position is specified.
On the other hand, as shown in FIG. 12, the first turning radius R5 is the same radius as the second turning radius R4. A circle 44 having a first turning radius R5 and in contact with the “straight line connecting the current position of the vehicle and the first reverse start position 33” and the “circle 43” from the second reverse start position 45 to the steered position P It is specified as a circle including the first half route that is the parking route up to. Further, the contact point between “circle 43” and “circle 44” becomes the steered position P of the second travel route 42, and “circle 44” and “a straight line connecting the current position of the vehicle and the first reverse start position 33” Is set at the second reverse start position 45.

  Next, in S27, the CPU 21 calculates the second travel route according to the parameters set in S22 to S26. Specifically, (a) a preparation path that advances from the current host vehicle position to the second reverse start position, and (b) a first half path that turns from the second reverse start position to the steered position by the first turning radius; (C) A combination of the second half route that turns from the steered position to the target position by the second turning radius is defined as the second traveling route.

Below, an example of the calculation process of the 2nd driving | running route performed by said S27 is demonstrated using FIG. In FIG. 13, the second traveling route 42 calculated when the second reverse start position 45, the target position 32, the first turning radius R5, and the second turning radius R4 shown in FIG. 12 are set will be described.
As shown in FIG. 13, the second travel route 42 includes a preparation route 46 that moves forward from the current host vehicle position to the second reverse start position 45, and a steered position P by the first turning radius R5 from the second reverse start position 45. And a first half path 47 that turns to the target position 32 from the steered position P by the second turning radius R4. Then, the vehicle 2 travels along the second travel route 42, thereby allowing the vehicle 2 to enter the target position 32 in the parking space 31 without any risk of contact with an obstacle. Note that S22 to S27 correspond to the processing of the second travel route calculation means.

As explained in detail above, in the parking assistance device 1 according to the present embodiment, the parking assistance method by the parking assistance device 1, and the computer program executed by the parking assistance device 1, the obstacle sensors 5A and 5B are around the vehicle. A parking space is detected (S1), a first travel route for parking the detected parking space at a predetermined turning rudder angle is calculated (S11 to S15), and a vehicle is further entered into the parking space. When the second travel route with the steering angle of the first travel route relaxed within the possible range is calculated (S22 to S27) and parking assistance is performed according to the calculated second travel route (S5). There is no risk that the vehicle will come into contact with obstacles around the parking space. Therefore, the relaxed route can reduce the driving burden on the driver and allow easy and safe parking.
Further, as a result of relaxing the rudder angle, when the total length of the second travel route becomes longer than necessary, it can be shortened to an appropriate distance (S24). As a result, the parking operation and the parking time can be simplified, and the parking space can be appropriately parked.

Note that the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the scope of the present invention.
For example, in this embodiment, the position of a parking space or an obstacle is detected by the obstacle sensors 5A and 5B, but may be detected using a radar device using a camera or a millimeter wave radar. Furthermore, the parking space may be stored in advance in a database.

  In the present embodiment, the travel route of the vehicle when performing parallel parking is calculated, but the travel route when performing parking other than parallel parking is calculated, and parking assistance is performed based on the calculated travel route. It's also good.

It is a schematic block diagram of the parking assistance apparatus which concerns on this embodiment. It is a block diagram which shows typically the control system of the parking assistance apparatus which concerns on this embodiment. It is a flowchart of the parking assistance guidance processing program which concerns on this embodiment. It is a flowchart of the sub process program of the 1st driving | running route calculation process which concerns on this embodiment. It is a flowchart of the sub process program of the 2nd driving | running route calculation process which concerns on this embodiment. It is explanatory drawing explaining an example of the setting process of the target position and the 1st reverse start position performed by step 11 and step 12. FIG. It is explanatory drawing explaining an example of the setting process of the 1st turning radius and 2nd turning radius performed by step 13 and step 14. FIG. It is explanatory drawing explaining an example of the 1st driving | running route calculation process performed at step 15. FIG. It is explanatory drawing explaining the calculation process of the 2nd turning radius of the 2nd driving | running route using the three square theorem. It is explanatory drawing explaining the calculation process of the 2nd turning radius of the 2nd driving | running route using a table. It is explanatory drawing explaining an example of the 2nd driving | running route which eased the steering angle of the 1st driving | running route and the 1st driving | running route. It is explanatory drawing explaining an example of the calculation process of the 1st turning radius performed at step 25, and the setting process of the 2nd reverse start position performed at step. It is explanatory drawing explaining an example of the calculation process of the 2nd driving | running route performed at step 27. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Parking assistance apparatus 2 Vehicle 3 Parking assistance ECU
5A, 5B Obstacle sensor 6 Liquid crystal display 7 Speaker 21 CPU
22 RAM
23 ROM

Claims (4)

Parking space detecting means for detecting the parking space;
First travel route calculation means for calculating a first travel route for causing the vehicle to enter the parking space detected by the parking space detection means at a predetermined steering angle;
Parking space shape acquisition means for acquiring the shape of the parking space;
Based on the shape of the parking space acquired by the parking space shape acquisition means, the steering angle of the first travel route calculated by the first travel route calculation means can be entered into the parking space. A second travel route calculating means for calculating a second travel route relaxed in the range;
A path total length determination unit that determines whether or not the total path length of the second travel path calculated by the second travel path calculation unit is longer than a predetermined distance;
When the route total length determining unit determines that the total length of the second travel route is longer than the predetermined distance, the second travel route is set so that the total length of the second travel route is equal to or less than the predetermined distance. Second travel route correction means for correcting,
A parking support device, comprising: parking support means for supporting parking based on the second travel route calculated by the second travel route calculation means and corrected by the second travel route correction means . The first travel route calculation means includes a second half route that turns from a steered position to a parking position in the parking space with a radius that allows entry into the parking space without contacting the vehicle or an obstacle, and a backward movement of the vehicle. A first half path that turns from a start position to the steered position, and calculates the first travel path,
The second travel route calculating means includes a second half route that turns from the steered position to the parking position with a maximum radius that can enter the parking space without contacting the vehicle or an obstacle, and a reverse start position of the vehicle. Calculating the second travel route including the first half route turning to the steered position,
The second travel route correction means reduces the turning radius of the second half route of the second travel route when the route total length determination means determines that the total length of the second travel route is longer than the predetermined distance. The parking assistance device according to claim 1 , wherein the second travel route is corrected such that the total length of the second travel route is equal to or less than a predetermined distance . A parking space detection step for detecting a parking space;
A first travel route calculating step for calculating a first travel route for causing the vehicle to enter the parking space detected in the parking space detecting step at a predetermined steering angle;
A parking space shape obtaining step for obtaining the shape of the parking space;
Based on the shape of the parking space acquired in the parking space shape acquisition step, the steering angle of the first travel route calculated in the first travel route calculation step can be entered into the parking space. A second travel route calculating step for calculating a second travel route relaxed in the range;
A path total length determining step for determining whether or not the total path length of the second travel path calculated by the second travel path calculating step is longer than a predetermined distance;
When the total length of the second travel route is determined to be longer than the predetermined distance in the total length determination step, the second travel route is set so that the total length of the second travel route is equal to or less than the predetermined distance. A second travel route correction step to be corrected;
A parking support method comprising: a parking support step for supporting parking based on the second travel route calculated by the second travel route calculation step and corrected by the second travel route correction step . On the computer ,
A parking space detection function for detecting a parking space;
A first travel route calculation function for calculating a first travel route for allowing the vehicle to enter the parking space detected by the parking space detection function at a predetermined steering angle;
A parking space shape acquisition function for acquiring the shape of the parking space;
Based on the shape of the parking space acquired by the parking space shape acquisition function, the steering angle of the first travel route calculated by the first travel route calculation function can be entered into the parking space. A second travel route calculation function for calculating a second travel route relaxed in the range;
A path total length determination function for determining whether or not the total path length of the second travel path calculated by the second travel path calculation function is longer than a predetermined distance;
When the route total length determination function determines that the total length of the second travel route is longer than the predetermined distance, the second travel route is set so that the total length of the second travel route is equal to or less than the predetermined distance. A second travel route correction function to correct;
A parking support function that supports parking based on the second travel route calculated by the second travel route calculation function and corrected by the second travel route correction function ;
A computer program for executing

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